I've got a Shell & Tube Heat exchanger with 4 3/4" thick tubesheets. (Stationary and Floating)
It's a Tema type AES exchanger -- 61" I.D. shell and channel with (2544) 3/4" o.d. Tubes on a 1" 45 degr. rotated sq. pitch.
It's all carbon steel, SA-516-70N except for the 410 S.Stl. Baffles. The tubes are welded SA-214 c.steel, Roller expanded only into the thubesheet.
It has a 5/16" corrosion allowance on the tubeside and runs at 308 psi @ 650 Degrees F. on the shellside and 308 psig @ 650 deg. F. on the tubeside.
My problem is the tubes are overstressed and I have no idea what are where to beef this thing up to eliminate the problem.
I apologize in advance for the length post, but all help is appreciate.